Magnesium Carbonate: A Recycled Coagulant—II

In the study leading to this article it was evident that the magnesium remaining in solution after coagulation was many times more than would be predicted by theory. There are several reasons for this discovered increase. In the jar tests, the time allowed for equilibrium was usually only 1 hr. In plant use, 4-6 hr are normally allowed for precipitation, which should decrease the magnesium remaining in solution. It is the magnesium hydroxide that precipitates that causes colloidal destabilization, and only this portion of the magnesium dosage can be recovered and reused.